''We are absolutely confident 25 megs is going to be enough - more than enough - for the average household.''

Opposition Leader Tony Abbott appears to have become quite the tech expert. In 2010 on the ABC's 7.30 Report, he struggled to explain his broadband policy or what megabits per second (Mbps) even meant, declaring himself ''no Bill Gates'' and no ''tech-head''. But announcing the Coalition's alternative NBN on Tuesday, Abbott was confident enough to proclaim 25 Mbps was all the speed we'd need, while Labor's 100 Mbps plan was an expensive white elephant.

But he could have more in common with Gates than he thinks. The Microsoft founder reportedly told a trade show in 1981 that 640 kilobytes of memory in computers ''ought to be enough for anybody''.

Years later Gates denied making the statement, but the phrase continues to haunt him. Similarly, to the tech geek Twitterati, Abbott's remarks have already been notched up alongside memorable short-sighted technology predictions like Digital Equipment Corp founder Ken Olsen's quip in 1977 that ''there is no reason for any individual to have a computer in his home''.

Technology has a habit of moving quicker than even the experts expect, and while Abbott is correct to say that 25 Mbps is enough to stream multiple high-definition movies (in some cases), tech commentators like Brad Howarth say ''the problem with designing a network to meet the needs of today is that it denies you the ability to meet the needs of tomorrow''.

Australia's peak science body CSIRO says essentially the more bandwidth the better, and smart geeks will always find innovative ways to make use of the capacity. The firm is already using the NBN to test a non-invasive monitoring and support system for elderly people, whose homes are fitted out with an array of sensors that can alert doctors and family to minute changes in behaviour or movement that may indicate a problem.

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In 2006, Melbourne computer programmer and tech pioneer Jon Oxer injected a microchip the size of a grain of rice into his arm. The chip, which is still working fine, allows him to open the front door of his fully automated house. Oxer says the NBN's 100 Mbps speeds could be immediately helpful in his various work projects quite apart from the consumer applications.

''It's a case of build it and ideas will come,'' Oxer said. ''I work from home on a wide range of projects, so every day I have to share large files including CAD files, high-res images, and video with customers and suppliers all over the world via the internet.''

Oxer also produces an online show called SuperHouseTV and it often takes eight hours or more to upload an episode as a high-definition video file to YouTube. ''If I could upload video more quickly, it would be much easier to publish episodes frequently, and perhaps to experiment with unusual show formats such as having interactive episodes involving viewers - like talkback TV.''

The kind of house automation that Oxer's family enjoys - he can wave the curtains open with his arm and if the smoke alarm goes off, the lights come on and the doors unlock - is growing in popularity. Daniel Baldwin, owner of audiovisual integrator InSight Systems in Melbourne, said clients were paying him more than $300,000 to kit out their homes with cutting-edge automation and entertainment technology.

''We did a job recently where they've got six different areas where they can watch content; there's a potential for six different people to be streaming content at once,'' he said.

Dr Mark Gregory, senior lecturer in electrical and computer engineering at RMIT University, said: ''In 20 years households will be highly automated and be permanently connected to the family members, pets and vehicles.''

Geoff Heydon, business development manager for CSIRO's Australian Centre for Broadband Innovation, said in the not too distant future people would have screens as big as a wall in their homes running multiple high-bandwidth apps. Sports fans could opt to stream five different angles of an event at once at super high resolution.

''These futures are very difficult to describe because we're not there yet, but the capability of the technology will be such that these options emerge,'' he said.

Ultra high-definition, also known as 4K TV, has already arrived, and while far from mainstream, it is only a matter of time before it replaces HD. A single 4K TV stream will require at least 25 Mbps of capacity, several experts said, and this ignores future advances in video resolution and the fact that in practice most households will have multiple people and devices using the network at once.

Earlier this week the Australian Bureau of Statistics revealed that Australians downloaded 526,472 terabytes (TB) of data on fixed lines in the quarter to December 2012, up from 174,665 TB in the quarter ending December 2010.

Akamai, which delivers 15-30 per cent of the world's internet traffic, said it expected its network to grow five times over the next three years, with 90 per cent of the traffic being video.

Akamai's senior manager for Australasia, Ian Teague, predicted that ''in the next couple of years … a single household would need streaming rates greater than 50 Mbps''.

And it's not just a way for geeks to download movies and porn faster. Professor Rod Tucker, director of the Institute for a Broadband-Enabled Society, said industries such as medicine and small businesses such as graphic designers, architects and consultants were dealing with an increasing quantity of data. Universities already had high band width connections, he said, but with the growth of online learning, students would need high-speed connections at home.

''It is not the single killer application that justifies 100 Mbps or more, it is all of the applications that run simultaneously,'' said Tucker, who was part of the expert panel the government chose to assess NBN proposals.

Futurist Mark Pesce believes in 10 years households will have ''north of 100 devices'' - from our lights and airconditioners to our toilets - all connected, and all sucking up bandwidth.

Labor's $37.4 billion fibre to the home (FTTH) plan is to connect 93 per cent of Australian households directly to optical fibre. For 71 per cent of homes, the Coalition plans to spend $20.4 billion connecting fibre only up to street cabinets (known as fibre to the node or FTTN), with the existing ageing copper network used for the last mile to the premises.

For the remaining households that cannot be serviced by fibre, both sides of politics now support using fixed wireless and satellite technologies.

Many applications, such as two-way high-resolution video chats and sending huge files to colleagues, require not only strong download speeds but fast upload speeds as well. Copper severely limits upload rates, but fibre, which can technically transfer data at the speed of light, has no such limitations.

Labor's argument is do it once, do it right, and its plan will offer the capability of up to 100 Mbps, with easy upgrades to 10 times that speed, 1Gbps, in the offing. However, the upfront labour costs are large and it is subject to delays.

The Coalition argues it is uneconomical to build such a high-capacity network before there is clear demand for it. It is offering a minimum 25 Mbps and claims most households will be connected to its cheaper NBN by 2017 as opposed to 2021.

Technology experts such as Geoff Huston, chief scientist at the Asia Pacific Network Information Centre, claim the Coalition's plan would see internet capacity frozen, and require the network be rebuilt down the track in order to connect fibre to the home.

The Coalition claims that even over existing copper they could deliver up to 100 Mbps in a second term, and the network could be upgraded to fibre to the home in future.

But is this feasible, and who will pay?

Networking experts polled by Fairfax derided the suggestion that Australia's ageing and corroded copper could deliver anywhere near 100 Mbps in practice. Telco engineer Mark Newton calls it ''faith-based network engineering''. In 2003 Telstra said its copper lines were ''five minutes to midnight''.

Tucker says the Coalition may be able to get 50 Mbps out of the copper and this was assuming it was not degraded, whereas Labor's network would be upgraded to 1 Gbps and beyond.

''The Coalition's is offering 5 per cent of Labor's speed. But the cost of the Coalition's network will be two-thirds of the cost of Labor's network,'' he says. ''It will be obsolete by the time it is completed.''

CSIRO's Heydon says fibre to the node requires much more electronics in more places than fibre to the home, and therefore ''the cost of maintaining and operating those cabinets out in the street is very high''.

While he does not want to comment on the politics, he says upgrading from FTTN to FTTH down the track may be prohibitively expensive as ''in many cases those nodes [cabinets] will become irrelevant when the copper's not there any more''.

The final cost of both plans remains up in the air, but you don't have to be a ''tech-head'' to see that the high maintenance and upgrade costs in the Coalition plan would bridge some of the expense gap between the two policies.